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<h1>src/qvip/qvmser.cpp</h1><a href="qvmser_8cpp.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment"> *      Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012. PARP Research Group.</span>
<a name="l00003"></a>00003 <span class="comment"> *      &lt;http://perception.inf.um.es&gt;</span>
<a name="l00004"></a>00004 <span class="comment"> *      University of Murcia, Spain.</span>
<a name="l00005"></a>00005 <span class="comment"> *</span>
<a name="l00006"></a>00006 <span class="comment"> *      This file is part of the QVision library.</span>
<a name="l00007"></a>00007 <span class="comment"> *</span>
<a name="l00008"></a>00008 <span class="comment"> *      QVision is free software: you can redistribute it and/or modify</span>
<a name="l00009"></a>00009 <span class="comment"> *      it under the terms of the GNU Lesser General Public License as</span>
<a name="l00010"></a>00010 <span class="comment"> *      published by the Free Software Foundation, version 3 of the License.</span>
<a name="l00011"></a>00011 <span class="comment"> *</span>
<a name="l00012"></a>00012 <span class="comment"> *      QVision is distributed in the hope that it will be useful,</span>
<a name="l00013"></a>00013 <span class="comment"> *      but WITHOUT ANY WARRANTY; without even the implied warranty of</span>
<a name="l00014"></a>00014 <span class="comment"> *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the</span>
<a name="l00015"></a>00015 <span class="comment"> *      GNU Lesser General Public License for more details.</span>
<a name="l00016"></a>00016 <span class="comment"> *</span>
<a name="l00017"></a>00017 <span class="comment"> *      You should have received a copy of the GNU Lesser General Public</span>
<a name="l00018"></a>00018 <span class="comment"> *      License along with QVision. If not, see &lt;http://www.gnu.org/licenses/&gt;.</span>
<a name="l00019"></a>00019 <span class="comment"> */</span>
<a name="l00020"></a>00020 
<a name="l00024"></a>00024 
<a name="l00025"></a>00025 <span class="preprocessor">#include &lt;QVMSER&gt;</span>
<a name="l00026"></a>00026 <span class="preprocessor">#include &lt;qvmath.h&gt;</span>
<a name="l00027"></a>00027 
<a name="l00028"></a><a class="code" href="group__qvip.html#ga782538a21f9e2ea0aef216b54cbf0570">00028</a> <span class="keywordtype">void</span> <a class="code" href="group__qvip.html#ga782538a21f9e2ea0aef216b54cbf0570" title="Obtains border contours for an MSER list, obtained with the function getMSER.">getMSERContours</a>(<span class="keyword">const</span> <a class="code" href="classQVImage.html">QVImage&lt;uChar, 1&gt;</a> &amp;image, <span class="keyword">const</span> QList&lt;QVMSER&gt; &amp;MSERList, QList&lt; QVPolyline &gt; &amp;polylineMSERList)
<a name="l00029"></a>00029         {
<a name="l00030"></a>00030         <span class="keyword">const</span> uInt rows = image.<a class="code" href="classQVImage.html#a55e71ad628f450ee82bb4226cb62ec17" title="Overloaded function from QVGenericImage::getRows().">getRows</a>(), cols = image.<a class="code" href="classQVImage.html#ad0f2758702ee4d96d538aa353ae81bb7" title="Overloaded function from QVGenericImage::getCols().">getCols</a>();
<a name="l00031"></a>00031 
<a name="l00032"></a>00032         <a class="code" href="classQVImage.html">QVImage&lt;uChar&gt;</a> notImage = image;
<a name="l00033"></a>00033         <span class="keywordflow">for</span> (uInt col = 0; col &lt; cols; col++)
<a name="l00034"></a>00034                 <span class="keywordflow">for</span> (uInt row = 0; row &lt; rows; row++)
<a name="l00035"></a>00035                         <span class="comment">// Weird: using the following line produces a core error:</span>
<a name="l00036"></a>00036                         <span class="comment">//notImage(col, row) = 255 - image(col, row);</span>
<a name="l00037"></a>00037                         notImage(col, row) = 255 - notImage(col, row);
<a name="l00038"></a>00038 
<a name="l00039"></a>00039         <span class="keywordflow">for</span> (<span class="keywordtype">int</span> msers = 0; msers &lt; MSERList.size(); msers++)
<a name="l00040"></a>00040                 {
<a name="l00041"></a>00041                 <a class="code" href="classQVPolyline.html" title="Polyline representation.">QVPolyline</a> polylineMSER = getConnectedSetBorderContourThreshold(notImage,
<a name="l00042"></a>00042                                                 MSERList.at(msers).seed,  255 - MSERList.at(msers).threshold);
<a name="l00043"></a>00043                 polylineMSERList.append (polylineMSER);
<a name="l00044"></a>00044                 }
<a name="l00045"></a>00045         }
<a name="l00046"></a>00046 
<a name="l00047"></a>00047 <span class="preprocessor">#define RELATIVE_DISTANCE(X,Y)  (ABS((X-Y)/(Y)))</span>
<a name="l00048"></a><a class="code" href="group__qvip.html#ga9eed952744ef9fc9a8b003c524f680f9">00048</a> <span class="preprocessor"></span><span class="keywordtype">void</span> <a class="code" href="group__qvip.html#ga9eed952744ef9fc9a8b003c524f680f9" title="This algorithm obtains MSER&amp;#39;s - from an image.This is an implementation of the...">getMSER</a>(<span class="keyword">const</span> <a class="code" href="classQVImage.html">QVImage&lt;uChar,1&gt;</a> &amp;image, QList&lt;QVMSER&gt; &amp;MSERList, <span class="keyword">const</span> <span class="keywordtype">int</span> delta, <span class="keyword">const</span> <span class="keywordtype">int</span> minArea, <span class="keyword">const</span> <span class="keywordtype">int</span> maxArea, <span class="keyword">const</span> <span class="keywordtype">double</span> diffAreaThreshold)
<a name="l00049"></a>00049         {
<a name="l00051"></a>00051         <span class="comment">// Prune low areas from image, with component tree</span>
<a name="l00052"></a>00052         <a class="code" href="classQVComponentTree.html" title="Image component tree data structure.">QVComponentTree</a> componentTree(image);
<a name="l00053"></a>00053 
<a name="l00055"></a>00055         <span class="comment">// Tree transversing</span>
<a name="l00056"></a>00056         uInt histogram[256];
<a name="l00057"></a>00057         <span class="keywordtype">double</span> q_function[256];
<a name="l00058"></a>00058 
<a name="l00059"></a>00059         <span class="keywordflow">for</span> (uInt node = 0; node &lt; componentTree.<a class="code" href="classQVComponentTree.html#afecb92bc570b9389428b6da484794ad6" title="Gets the number of total nodes in the tree.">getNumNodes</a>(); node++)
<a name="l00060"></a>00060                 {
<a name="l00061"></a>00061                 <span class="keywordtype">int</span> firstThres = componentTree.<a class="code" href="classQVComponentTree.html#af6f964ef20bf880f7aab393ec829e575" title="Returns gray-scale value of the points at the vertex of a node.">firstThreshold</a>(node), lastThres = componentTree.<a class="code" href="classQVComponentTree.html#ae1f6def9a17a983f3d2047eb564cc3ad" title="Returns gray-scale value of the points at the base of a node.">lastThreshold</a>(node);
<a name="l00062"></a>00062 
<a name="l00063"></a>00063                 <span class="keywordflow">if</span> (lastThres - firstThres - 2*delta - 2 &lt; 0)
<a name="l00064"></a>00064                         <span class="keywordflow">continue</span>;
<a name="l00065"></a>00065 
<a name="l00066"></a>00066                 <span class="comment">// We obtain histogram</span>
<a name="l00067"></a>00067                 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> threshold = firstThres; threshold &lt;= lastThres; threshold++)
<a name="l00068"></a>00068                                 {
<a name="l00069"></a>00069                                 uInt area = componentTree.<a class="code" href="classQVComponentTree.html#a270428438cc9b604e9261cf3c741c217" title="Returns the accumulative histogram of the gray-level values of the pixels, for a...">area</a>(node)[threshold], lastHistogramValue = 0 <span class="comment">/* esta variable no sería necesaria, se puede asignar area */</span>;
<a name="l00070"></a>00070                                 <span class="keywordflow">if</span>(area != 0)
<a name="l00071"></a>00071                                         lastHistogramValue = area;
<a name="l00072"></a>00072                                 histogram[threshold] = lastHistogramValue;
<a name="l00073"></a>00073                                 }
<a name="l00074"></a>00074 
<a name="l00075"></a>00075                 <span class="comment">// Calculate &#39;q&#39; function (from the paper)</span>
<a name="l00076"></a>00076                 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> threshold = firstThres + delta; threshold &lt;= lastThres - delta; threshold++)
<a name="l00077"></a>00077                         {
<a name="l00078"></a>00078                         q_function[threshold] = (double)(histogram[threshold + delta] - histogram[threshold - delta]) / histogram[threshold];
<a name="l00079"></a>00079                         }
<a name="l00080"></a>00080 
<a name="l00081"></a>00081                 <span class="comment">// Get local minima of the function, and append them to MSER list</span>
<a name="l00082"></a>00082                 <span class="keywordtype">int</span> lastMSERThreshold = -1, minLastMSERThreshold = 0;
<a name="l00083"></a>00083                 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> threshold = firstThres + delta + 1; threshold &lt;= lastThres - delta - 1; threshold++)
<a name="l00084"></a>00084                         {
<a name="l00085"></a>00085                         <span class="keywordflow">if</span> ( ((<span class="keywordtype">int</span>)histogram[threshold] &lt; minArea) || ((int)histogram[threshold] &gt; maxArea) )
<a name="l00086"></a>00086                                 <span class="keywordflow">continue</span>;
<a name="l00087"></a>00087 
<a name="l00088"></a>00088                         <span class="keywordflow">if</span> ( (q_function[threshold + 1] &gt; q_function[threshold]) &amp;&amp; (q_function[threshold - 1] &gt; q_function[threshold]) )
<a name="l00089"></a>00089                                 <span class="comment">// We have a minimum in the q function</span>
<a name="l00090"></a>00090                                 {
<a name="l00091"></a>00091                                 <span class="keywordflow">if</span> (lastMSERThreshold == -1)
<a name="l00092"></a>00092                                         <span class="comment">// We don&#39;t have any previous local minima in the node</span>
<a name="l00093"></a>00093                                         {
<a name="l00094"></a>00094                                         lastMSERThreshold = threshold;
<a name="l00095"></a>00095                                         minLastMSERThreshold = threshold;
<a name="l00096"></a>00096                                         }
<a name="l00097"></a>00097                                 <span class="keywordflow">else</span>
<a name="l00098"></a>00098                                         <span class="keywordflow">if</span> (RELATIVE_DISTANCE((<span class="keywordtype">float</span>)histogram[lastMSERThreshold], (float)histogram[threshold]) &lt; diffAreaThreshold)
<a name="l00099"></a>00099                                                 <span class="comment">// if distance with last minima isn&#39;t enough, we just actialize minimum MSER</span>
<a name="l00100"></a>00100                                                 {
<a name="l00101"></a>00101                                                 <span class="keywordflow">if</span> (q_function[minLastMSERThreshold] &gt; q_function[threshold])
<a name="l00102"></a>00102                                                                 minLastMSERThreshold = threshold;
<a name="l00103"></a>00103                                                 }
<a name="l00104"></a>00104                                         <span class="keywordflow">else</span>    <span class="comment">// We have a previous minima, and far enough from the actual minimum, we add the smallest MSER found in the previous set of minimums</span>
<a name="l00105"></a>00105                                                 {
<a name="l00106"></a>00106                                                 MSERList.append(<a class="code" href="classQVMSER.html" title="Maximally stable extremal region datatype.">QVMSER</a>(QPoint(componentTree.<a class="code" href="classQVComponentTree.html#a045219975a0145022d98c7fcf47642cb" title="Returns horizontal coordinate for the seed point of a node, given it&amp;#39;s index...">seedX</a>(node), componentTree.<a class="code" href="classQVComponentTree.html#ac763fa3f3de4beab5bdb072921965862" title="Returns vertical coordinate for the seed point of a node, given it&amp;#39;s index.">seedY</a>(node)), minLastMSERThreshold));
<a name="l00107"></a>00107                                                 lastMSERThreshold = threshold;
<a name="l00108"></a>00108                                                 minLastMSERThreshold = threshold;
<a name="l00109"></a>00109                                                 }
<a name="l00110"></a>00110                                 }
<a name="l00111"></a>00111                         }
<a name="l00112"></a>00112                 <span class="keywordflow">if</span> (lastMSERThreshold != -1)
<a name="l00113"></a>00113                         MSERList.append(<a class="code" href="classQVMSER.html" title="Maximally stable extremal region datatype.">QVMSER</a>(QPoint(componentTree.<a class="code" href="classQVComponentTree.html#a045219975a0145022d98c7fcf47642cb" title="Returns horizontal coordinate for the seed point of a node, given it&amp;#39;s index...">seedX</a>(node), componentTree.<a class="code" href="classQVComponentTree.html#ac763fa3f3de4beab5bdb072921965862" title="Returns vertical coordinate for the seed point of a node, given it&amp;#39;s index.">seedY</a>(node)), minLastMSERThreshold));
<a name="l00114"></a>00114                 }
<a name="l00115"></a>00115 
<a name="l00116"></a>00116         }
<a name="l00117"></a>00117 
</pre></div></div>
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<br /><hr><br />
<center><a href="http://perception.inf.um.es/QVision">QVision framework</a>.
<a href="http://perception.inf.um.es">PARP research group</a>.
Copyright &copy; 2007, 2008, 2009, 2010, 2011.</center>
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